>Is the mysterious object a projectile or a bird?
Bird. There are other videos as well:
https://twitter.com/DavidADaoud/status/1291039824263163909?s=20
https://www.bellingcat.com/news/mena/2020/08/07/the-beirut-explosion-is-it-a-bird-is-it-a-plane-is-it-a-faked-video-of-a-missile/